I've seen pictures of Chinese men welding with pigshit!

Okay, they weren't really welding with pigshit. The pigshit was in an oxcart which was covered by a big plastic bag. The methane from the pigshit inflated the bag and was pressurized so it would flow through the welding hoses by simply putting a brick or two on top of the bag, causing it to slowly collapse. Probably wouldn't get hot enough to weld stainless steel, but it'd probably do brazing and cutting just fine.